How much does commisioning a few peices of art of items cost?

A brief explanation: In my gaming sessions we use a diablo style inventory management, where every peice of loot is a small magnetic token, and your character sheet comes with a steel-paper bagpack and paper-doll with item slots, also in steel-paper.

These item tokens are made with images of what they are (swords, axes, armor and so on), and these images come mostly from RPG books i've bought as PDF's. The issue i have it that i can't find more than a single picture in the style i'm looking for of Pauldrons, and as we all know, pauldrons are an important piece of any heavy armor!

The question is, does anyone know where i should go find an artist to make something like this? and how much should i expect to have to pay for it. As it's purely for personal in-house use, the budget is somewhat limited.

I've attached a couple of pictures of the style i'm looking for. The pauldrons i already have a dragonscale cloakand a studdet leather armor

I know of an artist who does stuff like that for a living.
Be aware, its high quality and thus also expensive.

http://www.skullpaint.com/

If you want something less expensive, you are likely able to get something like your example pictures for about $10 when it is for personal use, although with items like these it really depends on the artist and it can be cheaper.
Just browse www.deviantart.com for a bit. Most artists there take commissions.

Have you tried other public access/royalty free art sites?

I've only tried google image search to find usable images. Do you have any suggestions of public access sites i could browse, that might contain what i'm looking for?